An antenna which establishes communication between an electronic key which an owner of a vehicle carries and a vehicle is provided on a smart entry system. A known antenna is described in JP2001-345615A.
The known antenna includes a ferrite member and an electric conductive wire. The antenna is made by coiling an electric conductive wire around a ferrite member, and is housed in a case which is made of resin. Potting material (i.e., resin) is injected into the case in order to hold the antenna and to waterproof the antenna.
Generally, ferrite includes low mechanical intensity and is likely to break. Accordingly, the antenna made of ferrite is required to be provided with resistance to vibration and resistance to impact by another means. Further, with an antenna including a core portion made of magnetic material other than ferrite, it is also favorable that the antenna is provided with resistance to vibration and resistance to impact considering that the antenna is mounted on a vehicle. With the known antenna described in JP2001-345615A, the ferrite member is protected from oscillation and impact by means of potting material injected into the case.
Notwithstanding, potting material requires cure time. In other words, a waiting time during which operation is not conducted is generated until the potting material is cured in a series of assembling operation from inserting the antenna in the case to holding the antenna in the case. Thus, in terms of a view for productivity (i.e., ease of assembly), there is room for improvement.
A need thus exists for an antenna device which can reduce man-hour for assembling an antenna.